Pedicle fixation into osteoporotic spine is tentative fixation at best, often leading to rapid, post operative loosening. Cement injection into the vertebral body (VB) has been utilized for osteoporotic compression fractures (vertebroplasty, kyphoplasty). Injection for augmentation of pedicle fixation is also done, utilizing the tapped pedicle screw hole as an access point.
Currently, however, there is no specific tool or safe system of injection/pressurization. Surgeons often use a cement-filled syringe with a large bore needle, or no needle at all. As such, cement cannot be placed under pressure into vertebral body utilizing a needle or syringe, thus affording minimal VB augmentation. Back flow risks cement flowing into the vertebral neural canal if the pedicle is medially violated. Retrograde flow out of the pedicle entry point may lead to spillage and cleanup problems.
With this background, there remains a need for delivery of cement or biological materials to augment the strength of the vertebral body in osteoporotic or otherwise weakened bone conditions, in preparation for pedicle fixation.